System, method and apparatus for self-cleaning dry etch

Abstract

A method for cleaning a processing chamber that includes heating an inner surface of the processing chamber to a first temperature. The first temperature can be sufficient to cause a first species to become volatile. The first species can be one of several species deposited on the inner surface. A cleaning chemistry is injected into the processing chamber. The cleaning chemistry can be reactive with a second one of the species to convert the second species to the first species. The volatilized first species can also be output from the processing chamber. A system for cleaning the process chamber is also described.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional application of and claims priority from U.S. patent application Ser. No. 10 / 802,460, filed Mar. 16, 2004 and entitled “System, Method and Apparatus for Self-Cleaning Dry Etch” which is incorporated herein by reference in its entirety for all purposes. U.S. patent application Ser. No. 10 / 802,460 is a continuation-in-part of and claims priority from U.S. patent application Ser. No. 10 / 390,117 filed on Mar. 14, 2003 and entitled “System, Method and Apparatus For Improved Global Dual-Damascene Planarization,” which is incorporated herein by reference in its entirety. U.S. patent application Ser. No. 10 / 802,460 is also a continuation-in-part of and claims priority from U.S. patent application Ser. No. 10 / 390,520 filed on Mar. 14, 2003 and entitled “System, Method and Apparatus For Improved Local Dual-Damascene Planarization,” which is incorporated herein by reference in its entirety. U.S. patent application S...

AI Technical Summary

Benefits of technology

[0009] Broadly speaking, the present invention fills these needs by providing a system and method for reducing the process chamber cleaning requirement. It should be appreciated that the present invention can be implemented in numerous ways, including as a process, an apparatus, a system, computer readable media, or a device. Several inventive embodiments of the present invention are described below.

[0023] A surface of the substrate can be etched at substantially the same time as the cleaning chemistry is present in the processing chamber. The cleaning chemistry can be operable to reduce the second one of the plurality of specie. The first species is at least one of a metal and halogen compound and a metal and oxygen compound, and wherein the second species is at least one of a non-volatile metal and a metal containing compound. The metal can include at least one of a group consisting of copper, tantalum, tungsten, platinum, iridium, ruthenium, hafnium, zirconium and aluminum.

[0025] Yet another embodiment provides a processing chamber including a plurality of inner surfaces, a plurality of deposits thereon, a substrate to be processed, a gas inlet, an outlet, a condensing surface proximate to the outlet, a heat source and a cleaning chemistry source coupled to the processing chamber. The heat source being capable heating at least one of the plurality of inner surfaces to a first temperature. The first temperature being sufficient to cause a first species to become volatile. The first species being one of a plurality of byproducts of a first process. The plurality of byproducts also including-a plurality of species deposited on the inner surface. The heat source is a plasma. The cleaning chemistry being reactive with a second one of the plurality of species to convert the second species to the first species and the condensing surface having a second temperature less than the first temperature. A surface of the substrate is etched at substantially the same time as the cleaning chemistry is present in the processing chamber. The cleaning chemistry is operable to reduce the second one of the plurality of specie.

[0027] The present invention provides the benefit of a reduced or substantially eliminated process chamber cleaning requirement and thereby increases the substrate throughput. The present invention also provides a more simplified cleaning process and cleaning chemistry than was previously utilized. The simplified cleaning chemistry can also decrease the financial cost of cleaning the process chamber.

[0028] The present invention also can substantially reduce process variability induced by plasma density change caused by deposits on inner surfaces of the plasma chamber. As a result the variability from substrate to substrate can be significantly reduced as well as enabling integrated processing of multi layered thin film stacks that have different sensitivities to plasma conditions. By way of example, a copper interconnect stack has copper barrier materials such as Ta / TaN and inter-metal dielectrics. This benefit can be extended to other applications such as etching of a MRAM stack

Problems solved by technology

The particles can contaminate the substrates being etched in the chamber.

The conductive byproduct deposits can also interfere with the operation of the plasma.

Due to this exposure, these parts ultimately erode or accumulate byproduct buildup, requiring replacement or thorough cleaning.

However, the cleaning and / or replacement costs of these lining parts can become very expensive both in actual cost and in lost production time required for the cleaning and replacement.

The frequent cleaning requirement reduces the time the process chamber can available for etching processes and thereby reduces the substrate throughput of the process chamber.

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